Fastener



FIG. 1 is a perspective view of a fastener showing my new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a left side elevation view thereof;

FIG. 5 is a right side elevation view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines in the drawings illustrate portions of the fastener that form no part of the claimed design. The dot-dot-dash broken lines in the drawings define the bounds of the claim and form no part thereof. None of the broken lines form any part of the claimed design. 

CLAIM The ornamental design for a fastener, as shown and described. 